Field of the Invention
The present invention relates to an intake system. More particularly, the present invention relates to an intake system which is configured to feed air into each cylinder through branched passages of the intake manifold by controlling air supplied into intake manifold by an air control valve.
Description of Related Art
In general, a diesel engine is provided with a turbo charger and an intercooler to obtain high output. The diesel engine with a turbo charger receives more external air by a compressor.
At this time, the external air received is compressed at a high temperature by heat generated in the compression process. Because this compressed air of high temperature (“supercharged air”) has a low density, the charging efficiency of an engine drops when the supercharged air is supplied into the engine.
Therefore, the engine may be provided with an intercooler to cool the supercharged air or to increase the density.
The intercooler is classified into an air-cooling intercooler and a water-cooling intercooler. The air-cooling intercooler is designed as a similar structure to that of a radiator. That is, the air-cooling intercooler cools the supercharged air that is supplied into the engine by using an air flowed while the vehicle is running. The water-cooling intercooler is an apparatus which cools the supercharged air using a coolant. Thus, the water-cooling intercooler has a merit of a higher responsiveness and cooling efficiency than the air-cooing intercooler.
A cooled air that is passed through the intercooler is supplied to the engine via an intake manifold.
The intake manifold can be integrally formed with the intercooler. The intake manifold formed integrally with intercooler has a merit of high cooling efficiency because the cooled air is directly supplied to the engine passing through the intake manifold. However, this intake manifold which is formed integrally with intercooler has a problem of an intake interference, because the intake manifold is communicated with all the cylinders, and it is difficult to supply the air to each cylinder equally.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.